CVE-2019-20791Public exploitNetwork attack vector

Memory corruption via unchecked network-name length

Published Apr 28, 2020 · Updated Aug 5, 2024

Stack-based buffer overflow in OpenThread before 2019-12-13 allows attackers to write beyond a stack buffer via an oversized network name. MeshCoP::Commissioner::GeneratePskc measures the supplied name with strlen and copies that many bytes into a fixed-size salt buffer without enforcing OT_NETWORK_NAME_MAX_SIZE. The NCP property handler can reach this path during commissioner PSKc generation; public OSS-Fuzz evidence demonstrates an out-of-bounds write but not code execution.

CVSS severity9.8
Critical
EPSS probability0.88%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in OpenThread before 2019-12-13 allows attackers to write beyond a stack buffer via an oversized network name. MeshCoP::Commissioner::GeneratePskc measures the supplied name with strlen and copies that many bytes into a fixed-size salt buffer without enforcing OT_NETWORK_NAME_MAX_SIZE. The NCP property handler can reach this path during commissioner PSKc generation; public OSS-Fuzz evidence demonstrates an out-of-bounds write but not code execution.

The record

CVE
CVE-2019-20791
Published
Apr 28, 2020
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 28, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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